Author Question: There is a 60 chance of getting stuck in traffic when leaving the city. On two separate days, what ... (Read 108 times)

Pineapplelove6 · **on:** Jun 24, 2018

There is a 60 chance of getting stuck in traffic when leaving the city. On two separate days, what is the probability that you get stuck in traffic both days?
a. .36
b. .60
c. 1.20
d. .30

Question 2

A random sample of 121 checking accounts at a bank showed an average daily balance of 280 . The standard deviation of the population is known to be 66.
a. Is it necessary to know anything about the shape of the distribution of the account balances in order to make an interval estimate of the mean of all the account balances? Explain.
b. Find the standard error of the mean.
c. Give a point estimate of the population mean.
d. Construct an 80 confidence interval for the population mean.
e. Construct a 95 confidence interval for the population mean.

Ksh22 · **Reply #1 on:** Jun 24, 2018

Answer to Question 1

a

Answer to Question 2

a. No, the sample is large and the standard deviation of the population is known.
b. 6
c. 280
d. 272.32 to 287.68
e. 268.24 to 291.76